Correct specification of a conditional quantile model implies that a particular conditional moment is equal to zero. We nonparametrically estimate the conditional moment function via series regression and test whether it is identically zero using uniform functional inference. Our approach is theoretically justified via a strong Gaussian approximation for statistics of growing dimensions in a general time series setting. We propose a novel bootstrap method in this nonstandard context and show that it significantly outperforms the benchmark asymptotic approximation in finite samples, especially for tail quantiles such as Value‐at‐Risk (VaR). We use the proposed new test to study the VaR and CoVaR (Adrian and Brunnermeier (2016)) of a collection of US financial institutions.
条件分位数模型的正确规范意味着特定的条件矩等于零。通过序列回归对条件矩函数进行非参数估计，并利用一致泛函推理检验其是否为同零。我们的方法在理论上是合理的，通过对一般时间序列设置中增长维度的统计的强高斯近似。在这种非标准环境下，我们提出了一种新的自举方法，并表明它在有限样本中显著优于基准渐近逼近，特别是对于尾部分位数，如Value - at - Risk (VaR)。我们使用提出的新测试来研究一组美国金融机构的VaR和CoVaR (Adrian and Brunnermeier(2016))。
{"title":"A consistent specification test for dynamic quantile models","authors":"Peter Horvath, Jia Li, Z. Liao, Andrew J. Patton","doi":"10.3982/qe1727","DOIUrl":"https://doi.org/10.3982/qe1727","url":null,"abstract":"Correct specification of a conditional quantile model implies that a particular conditional moment is equal to zero. We nonparametrically estimate the conditional moment function via series regression and test whether it is identically zero using uniform functional inference. Our approach is theoretically justified via a strong Gaussian approximation for statistics of growing dimensions in a general time series setting. We propose a novel bootstrap method in this nonstandard context and show that it significantly outperforms the benchmark asymptotic approximation in finite samples, especially for tail quantiles such as Value‐at‐Risk (VaR). We use the proposed new test to study the VaR and CoVaR (Adrian and Brunnermeier (2016)) of a collection of US financial institutions.","PeriodicalId":46811,"journal":{"name":"Quantitative Economics","volume":"1 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70361324","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Eran B. Hoffmann, Davide Malacrinò, Luigi Pistaferri
This paper summarizes statistics on the key aspects of the distribution of earnings levels and earnings changes using administrative (social security) data from Italy between 1985 and 2016. During the time covered by our data, earnings inequality and earnings volatility increased, while earnings mobility did not change significantly. We connect these trends with some salient facts about the Italian labor market, in particular the labor market reforms of the 1990s and 2000s, which induced a substantial rise in fixed‐term and part‐time employment. The rise in part‐time work explains much of the rise in earnings inequality, while the rise in fixed‐term contracts explains much of the rise in volatility. Both of these trends affect the earnings distribution through hours worked: part‐time jobs reduce hours worked within a week, while fixed‐term contracts reduce the number of weeks worked during the year as well as increase their volatility. We only find weak evidence that fixed‐term contracts represent a “stepping‐stone” to permanent employment. Finally, we offer suggestive evidence that the labor market reforms contributed to the slowdown in labor productivity in Italy by delaying human capital accumulation (in the form of general and firm‐specific experience) of recent cohorts.
{"title":"Earnings dynamics and labor market reforms: The Italian case","authors":"Eran B. Hoffmann, Davide Malacrinò, Luigi Pistaferri","doi":"10.3982/qe1865","DOIUrl":"https://doi.org/10.3982/qe1865","url":null,"abstract":"This paper summarizes statistics on the key aspects of the distribution of earnings levels and earnings changes using administrative (social security) data from Italy between 1985 and 2016. During the time covered by our data, earnings inequality and earnings volatility increased, while earnings mobility did not change significantly. We connect these trends with some salient facts about the Italian labor market, in particular the labor market reforms of the 1990s and 2000s, which induced a substantial rise in fixed‐term and part‐time employment. The rise in part‐time work explains much of the rise in earnings inequality, while the rise in fixed‐term contracts explains much of the rise in volatility. Both of these trends affect the earnings distribution through hours worked: part‐time jobs reduce hours worked within a week, while fixed‐term contracts reduce the number of weeks worked during the year as well as increase their volatility. We only find weak evidence that fixed‐term contracts represent a “stepping‐stone” to permanent employment. Finally, we offer suggestive evidence that the labor market reforms contributed to the slowdown in labor productivity in Italy by delaying human capital accumulation (in the form of general and firm‐specific experience) of recent cohorts.","PeriodicalId":46811,"journal":{"name":"Quantitative Economics","volume":"1 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70361451","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We develop a dynamic quantitative model of occupational choice and search frictions with multiple channels of intergenerational transmission (comparative advantage, social contacts, and preferences), and use it to decompose the occupational persistence observed in the UK. In the model, workers who choose their father's occupation find jobs faster and earn lower wages, which is consistent with patterns found in UK data. Quantitatively, parental networks account for 79% of total persistence. Shutting down parental networks or the transmission of preferences improves the allocation of workers, and thus yields welfare gains, while removing the transmission of comparative advantage generates welfare losses.
{"title":"Like father, like son: Occupational choice, intergenerational persistence and misallocation","authors":"Salvatore Lo Bello, Iacopo Morchio","doi":"10.3982/qe1375","DOIUrl":"https://doi.org/10.3982/qe1375","url":null,"abstract":"We develop a dynamic quantitative model of occupational choice and search frictions with multiple channels of intergenerational transmission (comparative advantage, social contacts, and preferences), and use it to decompose the occupational persistence observed in the UK. In the model, workers who choose their father's occupation find jobs faster and earn lower wages, which is consistent with patterns found in UK data. Quantitatively, parental networks account for 79% of total persistence. Shutting down parental networks or the transmission of preferences improves the allocation of workers, and thus yields welfare gains, while removing the transmission of comparative advantage generates welfare losses.","PeriodicalId":46811,"journal":{"name":"Quantitative Economics","volume":"1 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70360050","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We introduce the extended perturbation method, which improves the accuracy of standard perturbation by reducing approximation errors under certainty equivalence. For the New Keynesian model with Calvo pricing, extended perturbation is more accurate than standard perturbation, which implies explosive dynamics because it omits the upper bound on inflation implied by this model. In contrast, extended perturbation enforces this bound and generates stable dynamics. We also show that extended perturbation can accurately solve a New Keynesian model that enforces the zero lower bound for the monetary policy rate by considering a smooth nonlinear modification of the standard Taylor rule.
{"title":"The extended perturbation method: With applications to the New Keynesian model and the zero lower bound","authors":"Martin M. Andreasen, Anders F. Kronborg","doi":"10.3982/qe1102","DOIUrl":"https://doi.org/10.3982/qe1102","url":null,"abstract":"We introduce the extended perturbation method, which improves the accuracy of standard perturbation by reducing approximation errors under certainty equivalence. For the New Keynesian model with Calvo pricing, extended perturbation is more accurate than standard perturbation, which implies explosive dynamics because it omits the upper bound on inflation implied by this model. In contrast, extended perturbation enforces this bound and generates stable dynamics. We also show that extended perturbation can accurately solve a New Keynesian model that enforces the zero lower bound for the monetary policy rate by considering a smooth nonlinear modification of the standard Taylor rule.","PeriodicalId":46811,"journal":{"name":"Quantitative Economics","volume":"1 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70360298","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Juan Carlos Parra-Alvarez, Olaf Posch, Andreas Schrimpf
This paper shows that the consumption‐based capital asset pricing model (C‐CAPM) with low‐probability disaster risk rationalizes pricing errors. We find that implausible estimates of risk aversion and time preference are not puzzling if market participants expect a future catastrophic change in fundamentals, which just happens not to occur in the sample (a “peso problem”). A bias in structural parameter estimates emerges as a result of pricing errors in quiet times. While the bias essentially removes the pricing error in the simple models when risk‐free rates are constant, time‐variation may also generate large and persistent estimated pricing errors in simulated data. We also show analytically how the problem of biased estimates can be avoided in empirical research by resolving the misspecification in moment conditions.
{"title":"Peso problems in the estimation of the C‐CAPM","authors":"Juan Carlos Parra-Alvarez, Olaf Posch, Andreas Schrimpf","doi":"10.3982/qe1478","DOIUrl":"https://doi.org/10.3982/qe1478","url":null,"abstract":"This paper shows that the consumption‐based capital asset pricing model (C‐CAPM) with low‐probability disaster risk rationalizes pricing errors. We find that implausible estimates of risk aversion and time preference are not puzzling if market participants expect a future catastrophic change in fundamentals, which just happens not to occur in the sample (a “peso problem”). A bias in structural parameter estimates emerges as a result of pricing errors in quiet times. While the bias essentially removes the pricing error in the simple models when risk‐free rates are constant, time‐variation may also generate large and persistent estimated pricing errors in simulated data. We also show analytically how the problem of biased estimates can be avoided in empirical research by resolving the misspecification in moment conditions.","PeriodicalId":46811,"journal":{"name":"Quantitative Economics","volume":"1 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70360810","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper analyzes earnings inequality and earnings dynamics in Sweden over 1985–2016. The deep recession in the early 1990s marks a historic turning point with a massive increase in earnings inequality and earnings volatility, and the impact of the recession and the recovery from it lasted for decades. In the aftermath of the recession, we find steady growth in real earnings across the entire distribution for men and women and decreasing inequality over more than 20 years. Despite the positive trend, large gender differences in earnings dynamics persist. While earnings growth for men is more closely tied to the business cycle, women face much higher volatility overall. Earnings volatility is also substantially higher among foreign‐born workers, reflecting weaker labor market attachment and high risk of large negative shocks for low‐income immigrants. We document an important role of social benefits usage for the overall trends and for differences across subpopulations. Higher benefits enrollment, especially for women and immigrants, is associated with higher earnings volatility. As the generosity and usage of benefit programs declined over time, we find stronger earnings growth among low‐income workers, consistent with higher self‐sufficiency.
{"title":"Earnings dynamics of immigrants and natives in Sweden 1985–2016","authors":"Benjamin U. Friedrich, Lisa Laun, C. Meghir","doi":"10.3982/qe1854","DOIUrl":"https://doi.org/10.3982/qe1854","url":null,"abstract":"This paper analyzes earnings inequality and earnings dynamics in Sweden over 1985–2016. The deep recession in the early 1990s marks a historic turning point with a massive increase in earnings inequality and earnings volatility, and the impact of the recession and the recovery from it lasted for decades. In the aftermath of the recession, we find steady growth in real earnings across the entire distribution for men and women and decreasing inequality over more than 20 years. Despite the positive trend, large gender differences in earnings dynamics persist. While earnings growth for men is more closely tied to the business cycle, women face much higher volatility overall. Earnings volatility is also substantially higher among foreign‐born workers, reflecting weaker labor market attachment and high risk of large negative shocks for low‐income immigrants. We document an important role of social benefits usage for the overall trends and for differences across subpopulations. Higher benefits enrollment, especially for women and immigrants, is associated with higher earnings volatility. As the generosity and usage of benefit programs declined over time, we find stronger earnings growth among low‐income workers, consistent with higher self‐sufficiency.","PeriodicalId":46811,"journal":{"name":"Quantitative Economics","volume":"1 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70361236","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Does economic uncertainty promote the implementation of structural reforms? We answer this question using one of the most exhaustive cross‐country panel data sets on reforms in six major areas and measuring economic uncertainty with stock market volatility. To identify causality, we exploit exogenous differential variation in countries' exposure to foreign volatility shocks due to predetermined and time‐invariant bilateral characteristics. Across all specifications, we find that stock market volatility has a positive and significant effect on the adoption of reforms. This result is robust to the inclusion of a large number of controls, such as political variables, economic variables, crisis indicators, and a host of country, reform and time fixed effects, as well as across various approaches for accommodating heterogeneous trends and contemporaneous shocks. Overall, this evidence suggests that times of market turmoil, which are characterized by a high degree of uncertainty, may facilitate the implementation of reforms that would otherwise not pass.
{"title":"Economic uncertainty and structural reforms: Evidence from stock market volatility","authors":"Alessandra Bonfiglioli, Rosario Crinó, G. Gancia","doi":"10.3982/qe1551","DOIUrl":"https://doi.org/10.3982/qe1551","url":null,"abstract":"Does economic uncertainty promote the implementation of structural reforms? We answer this question using one of the most exhaustive cross‐country panel data sets on reforms in six major areas and measuring economic uncertainty with stock market volatility. To identify causality, we exploit exogenous differential variation in countries' exposure to foreign volatility shocks due to predetermined and time‐invariant bilateral characteristics. Across all specifications, we find that stock market volatility has a positive and significant effect on the adoption of reforms. This result is robust to the inclusion of a large number of controls, such as political variables, economic variables, crisis indicators, and a host of country, reform and time fixed effects, as well as across various approaches for accommodating heterogeneous trends and contemporaneous shocks. Overall, this evidence suggests that times of market turmoil, which are characterized by a high degree of uncertainty, may facilitate the implementation of reforms that would otherwise not pass.","PeriodicalId":46811,"journal":{"name":"Quantitative Economics","volume":"1 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70360494","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We study the impact of child work on cognitive development in four Low‐ and Middle‐Income Countries. We advance the literature by using cognitive test scores collected regardless of school attendance. We also address a key gap in the literature by controlling for children's complete time allocation budget. This allows us to estimate effects of different types of work, like chores and market/farm work, relative to specific alternative time‐uses, like school or study or play/leisure. Our results show child work is more detrimental to child development to the extent that it crowds out school/study time rather than leisure. We also show the adverse effect of time spent on domestic chores is similar to time spent on market and farm work, provided they both crowd out school/study time. Thus, policies to enhance child development should target a shift from all forms of work toward educational activities.
{"title":"Child work and cognitive development: Results from four low to middle income countries","authors":"Michael P. Keane, Sonya Krutikova, Timothy Neal","doi":"10.3982/qe1745","DOIUrl":"https://doi.org/10.3982/qe1745","url":null,"abstract":"We study the impact of child work on cognitive development in four Low‐ and Middle‐Income Countries. We advance the literature by using cognitive test scores collected regardless of school attendance. We also address a key gap in the literature by controlling for children's complete time allocation budget. This allows us to estimate effects of different types of work, like chores and market/farm work, relative to specific alternative time‐uses, like school or study or play/leisure. Our results show child work is more detrimental to child development to the extent that it crowds out school/study time rather than leisure. We also show the adverse effect of time spent on domestic chores is similar to time spent on market and farm work, provided they both crowd out school/study time. Thus, policies to enhance child development should target a shift from all forms of work toward educational activities.","PeriodicalId":46811,"journal":{"name":"Quantitative Economics","volume":"1 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70361332","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We construct a peer effects model where mean expenditures of consumers in one's peer group affect utility through perceived consumption needs. We provide a novel method for obtaining identification in social interactions models like ours, using ordinary survey data, where very few members of each peer group are observed. We implement the model using standard household‐level consumer expenditure survey microdata from India. We find that each additional rupee spent by one's peers increases perceived needs, and thereby reduces one's utility, by the equivalent of a 0.25 rupee decrease in one's own expenditures. These peer costs may be larger for richer households, meaning transfers from rich to poor could improve even inequality‐neutral social welfare, by reducing peer consumption externalities. We show welfare gains of billions of dollars per year might be possible by replacing government transfers of private goods to households with providing public goods or services, to reduce peer effects.
{"title":"Consumption peer effects and utility needs in India","authors":"Arthur Lewbel, S. Norris, K. Pendakur, X. Qu","doi":"10.3982/qe1760","DOIUrl":"https://doi.org/10.3982/qe1760","url":null,"abstract":"We construct a peer effects model where mean expenditures of consumers in one's peer group affect utility through perceived consumption needs. We provide a novel method for obtaining identification in social interactions models like ours, using ordinary survey data, where very few members of each peer group are observed. We implement the model using standard household‐level consumer expenditure survey microdata from India. We find that each additional rupee spent by one's peers increases perceived needs, and thereby reduces one's utility, by the equivalent of a 0.25 rupee decrease in one's own expenditures. These peer costs may be larger for richer households, meaning transfers from rich to poor could improve even inequality‐neutral social welfare, by reducing peer consumption externalities. We show welfare gains of billions of dollars per year might be possible by replacing government transfers of private goods to households with providing public goods or services, to reduce peer effects.","PeriodicalId":46811,"journal":{"name":"Quantitative Economics","volume":"1 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70361377","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper provides new stylized facts about labor earnings inequality and dynamics in France for the period 1991–2016. Using linked employer–employee data, we show that (i) labor inequality in France is low compared to other developed countries and has been decreasing until the financial crisis of 2009 and increasing since then, (ii) women experienced high earnings growth, in particular at the bottom of the distribution, in contrast to the stability observed for men. Both result from a decrease in labor costs at the minimum wage and an increase in the hourly minimum in the aftermath of the 35h workweek policy, (iii) top earnings (top 5 and 1%) grew moderately while very top earnings (top 0.1 and 0.01%) experienced a much higher growth, (iv) inequality between and within cohorts follow the same U‐shaped pattern as global inequality: it decreased before 2009 and then increased until 2016, (v) Individual earnings mobility is stable between 1991 and 2016, and very low at the top of the distribution, (vi) the distribution of earnings growth is negatively skewed, leptokurtic, and varies with age. Then, studying earnings dispersion both within and between territories, we document strong differences across cities as well as between urban and rural areas, even after controlling for observable characteristics. We also observe a continuous decrease in earnings inequality between territories. However, a larger inflation in rural territories mitigates this convergence. Finally, we document a strong reduction in inequality within rural and remote territories, again driven by changes at the bottom of the wage distribution.
{"title":"Inequality and earnings dynamics in France: National policies and local consequences","authors":"F. Kramarz, Elio Nimier-David, Thomas Delemotte","doi":"10.3982/qe1876","DOIUrl":"https://doi.org/10.3982/qe1876","url":null,"abstract":"This paper provides new stylized facts about labor earnings inequality and dynamics in France for the period 1991–2016. Using linked employer–employee data, we show that (i) labor inequality in France is low compared to other developed countries and has been decreasing until the financial crisis of 2009 and increasing since then, (ii) women experienced high earnings growth, in particular at the bottom of the distribution, in contrast to the stability observed for men. Both result from a decrease in labor costs at the minimum wage and an increase in the hourly minimum in the aftermath of the 35h workweek policy, (iii) top earnings (top 5 and 1%) grew moderately while very top earnings (top 0.1 and 0.01%) experienced a much higher growth, (iv) inequality between and within cohorts follow the same U‐shaped pattern as global inequality: it decreased before 2009 and then increased until 2016, (v) Individual earnings mobility is stable between 1991 and 2016, and very low at the top of the distribution, (vi) the distribution of earnings growth is negatively skewed, leptokurtic, and varies with age. Then, studying earnings dispersion both within and between territories, we document strong differences across cities as well as between urban and rural areas, even after controlling for observable characteristics. We also observe a continuous decrease in earnings inequality between territories. However, a larger inflation in rural territories mitigates this convergence. Finally, we document a strong reduction in inequality within rural and remote territories, again driven by changes at the bottom of the wage distribution.","PeriodicalId":46811,"journal":{"name":"Quantitative Economics","volume":"1 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70361003","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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